 (defn remove-mark-char
   [c]
   (mark->char c :nomark))
+

  (if (char? char)
    (mark->char (str char) mark)
    (let [c (remove-accent-char (string/lower-case char))
          current-accent (get-accent-char char)]
      (accent->char (to-case-of char
                                (mark->char* c mark) )
                       current-accent))))

    (string/upper-case c2)))

(defn single-vowel?
  [char]
  (let [c (str char)]
    (if (not= -1 (.indexOf SINGLE-VOWELS (string/lower-case c)))
      true
      false)))

(defn single-consonant?
  [c]
  (not  (single-vowel? c))
  )

(defn char->accent
  [char]
  (let [c (string/lower-case (str char))]
    (if (single-vowel? c)
      (ACCENTS (mod (.indexOf SINGLE-VOWELS c) 6))
      :none)))

(defn char->mark
  [char]
  (let [c (string/lower-case (str char))]
    (if (single-vowel? c)
      (let [vowel-index (.indexOf SINGLE-VOWELS c)]
        ([:none :breve :hat :none :hat :none
          :none :hat :horn :none :horn :none] (quot vowel-index 6)))
      (if (= "đ" c)
        :bar
        :none))))

(defn accent->char
  "Add mark to a character.
